Continuous carbon fiber reinforced Ti/Al_3Ti metal-intermetallic laminate (MIL) composites fabricated using ultrasonic consolidation assisted hot pressing sintering

摘要

A continuous carbon fiber reinforced Ti/Al3Ti metal-intermetallic laminate (C-f-Ti/Al3Ti MIL) composite was fabricated using an ultrasonic consolidation (UC) assisted hot pressing (HP) sintering technique. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were employed to characterize the microstructure of the UC-prepared laminate tapes (LT) and as-sintered C-f-Ti/Al3Ti MIL composite. The tensile and compressive mechanical properties of the C-f-Ti/Al3Ti MIL composites were measured. The results show that under a large normal force exerted by the sonotrode and severe transverse shear force transformed by the ultrasonic vibration, the C-f bundles could be separated into individual fibers and uniformly embedded into the Al foils surface layer without macroscopic defects. Using subsequent HP sintering, the C-f were successfully implanted into the Al3Ti matrix, and the mutual diffusion of the elements occurred between the fibers and the Al3Ti matrix, which indicated that the metallurgical bonding formed at the interface of the fiber/matrix during HP sintering. Furthermore, C-f-Ti/Al3Ti MIL composites exhibited better combinations of tensile and compressive properties than the MIL composite without the fiber reinforcement. The reinforcing mechanisms of the fibers are also discussed in detail.